Death, on a Pale Horse - S1.E7

The invasion by King Charles of France and Della Rovere proceeds with victory seemingly inevitable as the French sack the city of Lucca and the Italian powers flee to their banner, with Lucrezia's husband Giovanni Sforza poised to join them in the name of Milan; inventor Leonardo Da Vinci (guest star John Lynch) shows his drawings and blueprints for war machinery to the invaders.